Battery pack case and battery pack

ABSTRACT

The application relates to a battery pack case and a battery pack. The battery pack case includes: a bottom plate and a side plate connected with the bottom plate, the bottom plate and the side plate surround to form an accommodating portion configured to accommodate a unit cell; the bottom plate is provided with a plurality of first grooves and a plurality of second grooves opening toward the accommodating portion, the plurality of first grooves are spaced apart from each other, the plurality of second grooves are spaced apart from each other, and the first grooves and the second grooves are arranged to cross each other. The bottom plate of the battery pack itself has good rigidity, is not prone to warp deformation, and can prevent the overflow of structural glue from contaminating the wiring harness or electrical components.

CROSS-REFERENCE OF RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/CN2018/124616, filed on Dec. 28, 2018, which claims priority toChinese Patent Application No. 201820447239.7, filed on Mar. 30, 2018,both of which are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present application relates to the technical field of batteries, inparticular to a battery pack case and a battery pack.

BACKGROUND

With the development of technology, the application range of powerbatteries is getting wider and wider, involving production or life.Power batteries are also called as secondary batteries and arerechargeable batteries. Power batteries are widely used. Low-capacitypower batteries can be used in small electric vehicles, andhigh-capacity power batteries can be used in large electric vehicles,for example, hybrid vehicles or electric vehicles. When power batteriesare used in groups, bus bar is needed to be used to connect each powerbattery in series or in parallel. Power batteries are grouped to formbattery modules. Multiple battery modules are encapsulated by the packcase.

In the prior art, the bottom of the sheet metal pack case is flat, andits strength is poor. After the pack case is welded and the reinforcingbeam is welded, the flatness is greatly affected, and it is difficult toensure the flatness of the bottom of the pack case. At present, theflatness and strength of the lower pack case of the sheet metal batterypack are poor. When assembling the battery module, it is easy to causeunevenness of the power battery, which is not favorable to the weldingof the bus bar between the power batteries in the subsequent process,and virtual welding is easy to occur. When installing the batterymodule, glue needs to be coated on the bottom of the pack case to bondand fix the battery module. Due to the poor flatness of the bottom ofthe pack case, it is easy to cause uneven thickness of the glue layer.At the same time, the excess glue will also be squeezed by the bottom ofthe battery module and overflow to the surroundings. The excess gluewill stick to the wiring harness or electrical components, which willcause difficulties for the subsequent installation process andmaintenance.

SUMMARY

Embodiments of the present application provide a battery pack case and abattery pack. The bottom plate of the battery pack case itself includesgood rigidity, is not prone to warp deformation, and can prevent theoverflowing structural glue from contaminating the wiring harness orelectrical components.

In an aspect, an embodiment of the present application proposes abattery pack case, which comprises: a bottom plate and a side plateconnected to the bottom plate, the bottom plate and the side platesurround to define an accommodating portion configured to accommodate aunit cell; a plurality of first grooves and a plurality of secondgrooves opening toward the accommodating portion are provided on thebottom plate, the plurality of first grooves are spaced apart from eachother, the plurality of second grooves are spaced apart from each other,and the first grooves and the second grooves are arranged to cross eachother.

According to an aspect of an embodiment of the present application, thefirst grooves extend in a length direction of the bottom plate, and theplurality of first grooves are arranged in parallel, the second groovesextend in a width direction of the bottom plate, and the plurality ofsecond grooves are arranged in parallel.

According to an aspect of an embodiment of the present application, thefirst grooves and the second grooves are perpendicular to each other.

According to an aspect of the embodiment of the present application, asurface of the bottom plate facing away from the accommodating portionis further provided with first convex portions corresponding to thefirst grooves and second convex portions corresponding to the secondgrooves.

According to an aspect of an embodiment of the present application, thebattery pack case further comprises a plurality of reinforcing beams,and the plurality of reinforcing beams are spaced apart along the lengthdirection or width direction of the bottom plate.

According to an aspect of an embodiment of the present application, thebattery pack case further comprises a strip plate, the strip plate isdisposed at a connection between a long side of the bottom plate alongthe length direction of the bottom plate and the side plate, and thestrip plate comprises a first long side along the length direction ofthe bottom plate and a second long side along the length direction ofthe bottom plate opposite to each other, the first long side isconnected and fixed to the side plate, and the second long side isconnected and fixed to the long side of the bottom plate.

According to an aspect of the embodiment of the present application, asurface of the second long side facing away from the bottom plate islower than a surface of the bottom plate facing the accommodatingportion, the strip plate further comprises a plurality of first gluereceiving grooves provided on the second long side, the plurality offirst glue receiving grooves are arranged at intervals along the lengthdirection of the bottom plate.

According to an aspect of an embodiment of the present application, thebattery pack case further comprises a supporting beam, the supportingbeam is disposed on a surface of the bottom plate facing theaccommodating portion, the supporting beam comprises a first connectingsection, an intermediate supporting section and a second connectingsection that are successively distributed, the first connecting sectionis connected and fixed to the side plate or a wide side of the bottomplate along the width direction of the bottom plate, the secondconnecting section is connected and fixed to the wide side of the bottomplate, and the intermediate supporting section is configured to installthe unit cell.

According to an aspect of an embodiment of the present application, theintermediate supporting section protrudes away from the bottom plate,and comprises a top surface parallel to the surface of the bottom platefacing the accommodating portion, and a fixing hole provided on the topsurface and configured to fix the unit cell.

According to an aspect of an embodiment of the present application, asurface of the second connecting section facing away from the bottomplate is lower than a surface of the bottom plate facing theaccommodating portion, the supporting beam further comprises a pluralityof second glue receiving grooves provided on the second connectingsection, and the second glue receiving grooves are arranged at intervalsalong the width direction of the bottom plate.

According to the battery pack case provided by the embodiment of thepresent application, the first grooves and the second grooves areprovided on the bottom plate. On the one hand, it can improve thestrength and rigidity of the bottom plate, thereby avoiding warpdeformation of the bottom plate, ensuring that the bottom platemaintains good flatness, and further ensuring that the tops of themultiple unit cells installed and fixed on the bottom plate are flush,which is favorable to welding operation of the bus bar on two adjacentunit cells. On the other hand, the first grooves and the second groovescan be used to collect the excess structural glue squeezed out by theunit cell, so as to avoid the structural glue from overflowing andcontaminating the wiring harness or other electrical components, orcausing the wiring harness or other electrical components to stick toeach other, which is convenient for subsequent maintenance orreplacement of wiring harness or electrical components.

In another aspect, an embodiment of the present application provides abattery pack, which comprises: a battery pack case comprising a bottomplate and a side plate connected to the bottom plate, the bottom plateand the side plate surround to define an accommodating portionconfigured to accommodate a unit cell, a plurality of first grooves anda plurality of second grooves opening toward the accommodating portionare provided on the bottom plate, the plurality of first grooves arespaced apart from each other, the plurality of second grooves are spacedapart from each other, and the first grooves and the second grooves arearranged to cross each other; a plurality of battery assemblies, whichare provided in the accommodating portion and supported by the bottomplate, and the plurality of battery assemblies are arranged side by sidealong the width direction of the bottom plate, each of the batteryassemblies comprises a plurality of unit cells arranged side by sidealong the length direction of the bottom plate.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, advantages, and technical effects of exemplary embodimentsof the present application will be described below with reference to thedrawings.

FIG. 1 is a schematic diagram of the overall structure of a battery packcase according to an embodiment of the present application;

FIG. 2 is a schematic diagram of the back structure of a battery packcase according to an embodiment of the present application;

FIG. 3 is a schematic diagram of the front structure of a battery packcase according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a sectional structure of a battery packcase according to an embodiment of the present application along thelength direction;

FIG. 5 is a partial enlarged view at A in FIG. 4;

FIG. 6 is a schematic diagram of a sectional structure of a battery packcase according to an embodiment of the present application along thewidth direction;

FIG. 7 is a schematic diagram of a connection structure of a strip plateand a supporting beam according to an embodiment of the presentapplication.

In the drawings, the drawings are not drawn to actual scale.

REFERENCE DESCRIPTION

-   -   1. bottom plate; 11. first groove; 12. second groove; 13. first        convex portion; 14. second convex portion;    -   2. side plate;    -   3. accommodating portion;    -   4. reinforcing beam;    -   5. strip plate; 51. first long side; 52. second long side; 53.        first glue receiving groove;    -   6. supporting beam; 61. first connecting section; 62.        intermediate supporting section; 62 a. fixing hole; 63. second        connecting section; 64. second glue receiving groove;    -   X length direction; Y width direction.

DETAILED DESCRIPTION

The implementation of the present application will be described infurther detail below with reference to the drawings and embodiments. Thedetailed description and drawings of the following embodiments are usedto exemplarily illustrate the principle of the present application, butcannot be used to limit the scope of the present application, that is,the present application is not limited to the described embodiments.

In the description of this application, it need to be noted that, unlessotherwise stated, the meaning of “plurality” is two or more; the terms“upper”, “lower”, “left”, “right”, “inner”, “outside” and otherindicating orientations or positional relationships are only for theconvenience of describing the present application and simplifying thedescription, rather than indicating or implying that the device orelement referred to must have a specific orientation, be constructed andoperated in a specific orientation, and therefore cannot be understoodas a limitation to the present application. In addition, the terms“first”, “second”, etc. are used for descriptive purposes only, andcannot be understood as indicating or implying relative importance.

In the description of this application, it need also be noted that,unless otherwise clearly specified and limited, the terms “install”, “beconnected with”, and “connect” should be understood in a broad sense,for example, it can be fixed connected or detachably connected, orintegrally connected; it can be either directly connected or indirectlyconnected through an intermediary. For those of ordinary skill in theart, the specific meanings of the above terms in the present applicationmay be understood according to specific circumstances.

In order to better understand the present application, the battery packcase of the embodiment of the present application will be described indetail below with reference to FIGS. 1 to 7.

FIG. 1 schematically shows the overall structure of the battery packcase of the present embodiment. FIG. 2 schematically shows the backstructure of the battery pack case of the present embodiment. FIG. 3schematically shows the front structure of the battery pack case of thepresent embodiment. FIG. 4 schematically shows the sectional structureof the battery pack case of the present embodiment along the lengthdirection. FIG. 5 schematically shows a partially enlarged structure atA in FIG. 4. FIG. 6 schematically shows a sectional structure of thebattery pack case of the present embodiment in the width direction. FIG.7 schematically shows the connection structure of the strip plate andthe supporting beam of the present embodiment.

The battery pack case of the present application is used to accommodatea unit cell (not shown in the figures) to form protection for the unitcell. At the same time, it can also accommodate the wiring harness orother electronic components related to the use of the unit cell andprotect them. The unit cell of the present embodiment may be a squarebattery.

As shown by combining FIGS. 1 to 3, the battery pack case of the presentembodiment includes a bottom plate 1 and a side plate 2 connected to thebottom plate 1. The bottom plate 1 and the side plate 2 surround to forman accommodating portion 3 for accommodating the unit cell. The unitcell is put into the battery pack case through the opening of theaccommodating portion 3. The bottom plate 1 is provided with a pluralityof first grooves 11 and a plurality of second grooves 12 opening towardthe accommodating portion 3. The plurality of first grooves 11 arespaced apart from each other. The plurality of second grooves 12 arespaced apart from each other. The first grooves 11 and the secondgrooves 12 cross each other to form a grid-like structure.

On the one hand, an area for supporting the unit cell is divided betweentwo adjacent first grooves 11 and two adjacent second grooves 12. Thebottom of the unit cell is seated in this area. The first grooves 11 andthe second grooves 12 crossing each other on the bottom plate 1 canimprove the rigidity of the bottom plate 1 so that the bottom plate 1 isnot prone to warp deformation due to its own internal stress, therebyensuring the flatness of a surface of the bottom plate 1 facing theaccommodating portion 3. In this way, when all the unit cells areinstalled in the battery pack case, the top height of all the unit cellsare kept flush to avoid unevenness situation, which is favorable tostably welding the bus bar on the output electrodes of two adjacent unitcells in the subsequent process and ensures the welding stability of thebus bar and the output electrode during subsequent use.

On the other hand, an area for supporting the unit cell is dividedbetween two adjacent first grooves 11 and two adjacent second grooves12. Before the unit cell is installed, a predetermined amount ofstructural glue needs to be applied in this area. Since the bottom plate1 includes good flatness, it can ensure that the thickness of thestructural glue applied on the bottom plate 1 is uniform. In addition,during the installation of the unit cell, the structural glue issqueezed by the unit cell and flows around. The structural glue that issqueezed and overflowed by the unit cell can flow to the first grooves11 and the second grooves 12 and be received and collected by the firstgrooves 11 and the second grooves 12 to avoid the overflow of excessstructural glue and contaminating of the wiring harness or otherelectrical components, or causing the wiring harness or other electricalcomponents to stick to each other, which is convenient for subsequentmaintenance or replacement.

The bottom plate 1 of the present embodiment includes a predeterminedlength and width. The first grooves 11 extend in a length direction X ofthe bottom plate 1, and a plurality of first grooves 11 are arranged inparallel. The second grooves 12 extend in a width direction Y of thebottom plate 1, and a plurality of second grooves 12 are arranged inparallel. In this way, the first grooves 11 and the second grooves 12divide the area of the bottom plate 1 in a more orderly manner, andfurther improve the rigidity of the bottom plate 1 itself.Alternatively, the plurality of first grooves 11 are arranged inparallel at equal intervals. The plurality of second grooves 12 arearranged in parallel at equal intervals. The plurality of first grooves11 and the plurality of second grooves 12 divide a plurality of areasfor supporting the unit cells. The area of each area is the same, sothat the overall force of the bottom plate 1 is balanced, and thecapability of resisting deformation is improved.

In one embodiment, the first grooves 11 and the second grooves 12 areperpendicular to each other. The area divided by the two adjacent firstgrooves 11 and the two adjacent second grooves 12 is rectangular. Thefirst grooves 11 are perpendicular to a wide side of the bottom plate 1,which can prevent the wide side of the bottom plate 1 from warpdeformation. The second grooves 12 are perpendicular to a long side ofthe bottom plate 1, which can prevent the long side of the bottom plate1 from warp deformation. The first grooves 11 and the second grooves 12which are perpendicular to each other are easy to process andmanufacture.

As shown by combining FIG. 2 and FIG. 4, a surface of the bottom plate 1of the present embodiment facing away from the accommodating portion 3is further provided with first convex portions 13 corresponding to thefirst grooves 11 and second convex portions 14 corresponding to thesecond grooves 12. The first convex portions 13 and the second convexportions 14 can further increase the rigidity and the strength of thebottom plate 1 and withstand greater stress without deformation. In oneexample, the bottom plate 1 can be manufactured with the first grooves11 and the second grooves 12 by stamping or mold pressing, or the firstgrooves 11, the first convex portions 13, the second grooves 12 and thesecond convex portions 14 are manufactured at the same time.Alternatively, the cross-sectional shapes of the first grooves 11 andthe second grooves 12 are the same, and both are arc-shaped or U-shaped.The cross-sectional shape of the first convex portions 13 is the same asthe cross-sectional shape of the first grooves 11, and thecross-sectional shape of the second convex portions 14 is the same asthe cross-sectional shape of the second grooves 12.

The battery pack case of the present embodiment further includes aplurality of reinforcing beams 4. The plurality of reinforcing beams 4are arranged at intervals along the length direction X or the widthdirection Y of the bottom plate 1. The reinforcing beams 4 are connectedto the bottom plate 1 and the side plate 2 at the same time. A pluralityof reinforcing beams 4 can reinforce the bottom plate 1 and the sideplate 2 from the outside of the battery pack case, and improve theoverall rigidity and strength of the battery pack case, therebyimproving the overall impact resistance of the battery pack case so thatthe bottom plate 1 and the side plate 2 are not easy to be deformed byexternal force, ensuring the stability of the position of the unit cellscontained inside and the stability of the connection between each other,and improving the safety of the use process. Alternatively, thereinforcing beams 4 may be welded to the bottom plate 1 and the sideplate 2 or may be connected and fixed by fasteners.

As shown by combining FIG. 6 and FIG. 7, the battery pack case of thepresent embodiment further includes a strip plate 5. The strip plate 5is provided at the connection between the long side of the bottom plate1 and the side plate 2. One strip plate 5 is respectively arrangedbetween the two opposite long sides of the bottom plate 1 and the sideplate 2. The strip plate 5 extends along the length direction X of thebottom plate 1. The strip plate 5 includes a first long side 51 and asecond long side 52 opposite to each other. The first long side 51 isconnected and fixed to the side plate 2. The second long side 52 isconnected and fixed to the long side of the bottom plate 1. The stripplate 5 can further improve the overall rigidity and strength of thebattery pack case. Alternatively, the cross-sectional shape of the stripplate 5 is L-shaped. The first long side 51 is welded to the side plate2, and the second long side 52 is welded to the bottom plate 1.

A surface of the second long side 52 of the present embodiment facingaway from the bottom plate 1 is lower than the surface of the bottomplate 1 facing the accommodating portion 3, so as to avoid the bottom ofthe unit cell from being seated on the surface of the second long side52 facing away from the bottom plate 1 and a gap from occurring betweenit and the surface of the bottom plate 1 facing the accommodatingportion 3, causing deterioration of the stability of the unit cell. Thestrip plate 5 further includes a plurality of first glue receivinggrooves 53 disposed on the second long side 52. A plurality of firstglue receiving grooves 53 are arranged at intervals along the lengthdirection X of the bottom plate 1. When the unit cell is installed onthe bottom plate 1, the structural glue squeezed by the unit celladjacent to the side plate 2 in the width direction Y of the bottomplate 1 may flow into the first glue groove 53 to avoid the structureglue from flowing in any direction and causing wire harnesses orelectrical components to stick. Alternatively, the shape of the firstglue receiving groove 53 is V-shaped or U-shaped.

As shown by combining FIG. 5 and FIG. 7, the battery pack case of thepresent embodiment further includes a supporting beam 6. The supportingbeam 6 is provided on the surface of the bottom plate 1 facing theaccommodating portion 3. The bottom plate 1 includes two opposite widesides. One supporting beam 6 is respectively provided on the two widesides of the bottom plate 1. The supporting beam 6 extends in the widthdirection Y of the bottom plate 1. The supporting beam 6 includes afirst connecting section 61, an intermediate supporting section 62, anda second connecting section 63 that are successively distributed alongthe length direction X of the bottom plate 1. The first connectingsection 61 is connected and fixed to the side plate 2 or the wide sideof the bottom plate 1. The second connecting section 63 is connected andfixed to the wide side of the bottom plate 1. The intermediatesupporting section 62 is used to install and fix the unit cell.

In one embodiment, the intermediate supporting section 62 protrudes awayfrom the bottom plate 1. The intermediate supporting section 62 includesa top surface parallel to the surface of the bottom plate 1 facing theaccommodating portion 3, and a fixing hole 62 a provided on the topsurface and used to fix the unit cell. The top surface of theintermediate supporting section 62 is higher than the surface of thebottom plate 1 facing the accommodating portion 3. The unit cell isdisposed between the two supporting beams 6, and its installation andfixation are realized by the connecting component connected to the twosupporting beams 6 at the same time. Alternatively, the fixing hole 62 ais a screw hole. The connecting component includes a screw rod connectedto the screw of the fixing hole 62 a.

In one embodiment, a surface of the second connecting section 63 facingaway from the bottom plate 1 is lower than the surface of the bottomplate 1 facing the accommodating portion 3, so as to avoid interferenceof the second connecting section 63 in the installation and fixingprocess of the unit cell. The top surface of the intermediate supportingsection 62 is higher than the surface of the second connecting section63 facing away from the bottom plate 1. The supporting beam 6 furtherincludes a plurality of second glue receiving grooves 64 provided on thesecond connecting section 63. The plurality of second glue receivinggrooves 64 are arranged at intervals along the width direction Y of thebottom plate 1. When the unit cell is installed on the bottom plate 1,the structural glue squeezed by the unit cell adjacent to the side plate2 in the length direction X of the bottom plate 1 may flow into thesecond glue receiving grooves 64, thereby avoiding the structure gluefrom flowing in any direction, which causes the wire harnesses orelectrical components to stick. Alternatively, the shape of the secondglue receiving groove 64 is V-shaped or U-shaped.

In the battery pack case of the embodiment of the present application,the first grooves 11 and the second grooves 12 are provided on thebottom plate 1. On the one hand, the strength and rigidity of the bottomplate 1 can be improved so as to avoid warp deformation of the bottomplate 1, ensuring that the bottom plate 1 maintains a good flatness, andfurther ensuring that the tops of the plurality of unit cells installedand fixed on the bottom plate 1 are flush, which is favorable to thewelding operation of the bus bar on two adjacent unit cells. On theother hand, the first grooves 11 and the second grooves 12 can be usedto collect excess structural glue that is squeezed out by the unit cellso as to avoid the structural glue from overflowing and contaminatingthe wiring harness or other electrical components, or causing the wiringharness or other electrical components to stick to each other, whichfacilitates subsequent maintenance or the replacement of the wiringharness or electrical components.

An embodiment of the present application further proposes a batterypack, including the battery pack case of the foregoing embodiment and aplurality of battery assemblies provided in the battery pack case. Aplurality of battery assemblies are arranged side by side along thewidth direction Y of the bottom plate 1. Each of the battery assembliesincludes a plurality of unit cells arranged side by side along thelength direction X of the bottom plate 1. The unit cell is bonded to thebottom plate 1 of the battery pack case through structural glue. Sincethe flatness of the bottom plate 1 of the battery pack case is good,unevenness phenomenon may not occur on the top of each of the pluralityof unit cells. The battery pack case includes good overall rigidity andstrong impact resistance, thereby effectively protecting the unit cell.

Although the present application has been described with reference tothe preferred embodiments, various improvements can be made andcomponents therein can be replaced with equivalents without departingfrom the scope of the present application. In particular, as long asthere is no structural conflict, the technical features mentioned in thevarious embodiments can be combined in any way. This application is notlimited to the specific embodiments disclosed herein, but includes alltechnical solutions falling within the scope of the claims.

1. A battery pack case, comprising: a bottom plate and a side plateconnected to the bottom plate, wherein the bottom plate and the sideplate surround to define an accommodating portion configured toaccommodate a unit cell; a plurality of first grooves and a plurality ofsecond grooves opening toward the accommodating portion are provided onthe bottom plate, wherein the plurality of first grooves are spacedapart from each other, the plurality of second grooves are spaced apartfrom each other, and the first grooves and the second grooves arearranged to cross each other.
 2. The battery pack case according toclaim 1, wherein the first grooves extend in a length direction of thebottom plate, and the plurality of first grooves are arranged inparallel, and the second grooves extend in a width direction of thebottom plate, and the plurality of second grooves are arranged inparallel.
 3. The battery pack case according to claim 2, wherein thefirst grooves and the second grooves are perpendicular to each other. 4.The battery pack case according to claim 1, wherein a surface of thebottom plate facing away from the accommodating portion is furtherprovided with a plurality of first convex portions corresponding to thefirst grooves and a plurality of second convex portions corresponding tothe second grooves.
 5. The battery pack case according to claim 1,wherein the battery pack case further comprises a strip plate, the stripplate is disposed at a connection between a long side of the bottomplate along a length direction of the bottom plate and the side plate,the strip plate comprises a first long side along the length directionof the bottom plate and a second long side along the length direction ofthe bottom plate opposite to each other, the first long side isconnected and fixed to the side plate, and the second long side isconnected and fixed to the long side of the bottom plate.
 6. The batterypack case according to claim 5, wherein a surface of the second longside facing away from the bottom plate is lower than a surface of thebottom plate facing the accommodating portion, the strip plate furthercomprises a plurality of first glue receiving grooves provided on thesecond long side, and the plurality of first glue receiving grooves arearranged at intervals along the length direction of the bottom plate. 7.The battery pack case according to claim 1, wherein the battery packcase further comprises a supporting beam provided on a surface of thebottom plate facing the accommodating portion, the supporting beamcomprises a first connecting section, an intermediate supporting sectionand a second connecting section successively distributed, the firstconnecting section is connected and fixed to the side plate or a wideside of the bottom plate along a width direction of the bottom plate,and the second connecting section is connected and fixed to the wideside of the bottom plate, the intermediate supporting section isconfigured to install the unit cell.
 8. The battery pack case accordingto claim 7, wherein the intermediate supporting section protrudes awayfrom the bottom plate, the intermediate supporting section comprises atop surface parallel to a surface of the bottom plate facing theaccommodating portion and a fixing hole provided on the top surface andconfigured to fix the unit cell.
 9. The battery pack case according toclaim 7, wherein a surface of the second connecting section facing awayfrom the bottom plate is lower than a surface of the bottom plate facingthe accommodating portion, the supporting beam further comprises aplurality of second glue receiving grooves provided on the secondconnecting section, the plurality of second glue receiving grooves arearranged at intervals along the width direction of the bottom plate. 10.A battery pack, comprising: a battery pack case comprising a bottomplate and a side plate connected to the bottom plate, wherein the bottomplate and the side plate surround to define an accommodating portionconfigured to accommodate a unit cell, a plurality of first grooves anda plurality of second grooves opening toward the accommodating portionare provided on the bottom plate, the plurality of first grooves arespaced apart from each other, the plurality of second grooves are spacedapart from each other, and the first grooves and the second grooves arearranged to cross each other; a plurality of battery assemblies providedin the accommodating portion and supported by the bottom plate, theplurality of battery assemblies are arranged side by side along a widthdirection of the bottom plate, and each of the battery assembliescomprises a plurality of unit cells arranged side by side in a lengthdirection of the bottom plate.